The techniques of phased-array radars are well known in the literature. Typically, antenna elements in such a radar emit separate microwave signals. When all the elements radiate precisely in phase, yielding wave crests that move forward in step, the waves become superimposed along the perpendicular axis of the array. They interfere constructively to produce a strong sum signal, resulting in a beam directed straight ahead. If the signals from each of the radiating elements are delayed electronically by amounts that increase steadily across the face of the array, the delays will cause a signal to lag a fraction of a wavelength behind the signal from an adjacent element. This moves the constructive strong signal to one side. Thus, by changing the phase of the emitters the point of strongest signal can be steered. This technique is used in the present invention to steer a set of points of coherent light so that they may irradiate a photochromic surface along linear paths.
A U.S. patent to Gillis et al, U.S. Pat. No. 4,111,519 teaches an apparatus for recording and reading synthetic holograms. This apparatus describes a method for recording a byte of binary data as a synthetic Fourier transform hologram. A U.S. patent to Caulfied U.S. Pat. No. 4,498,740 describes an apparatus and method for writing a hologram from x, y, and z coordinates.
The above patents and the prior art in general does not show a method and apparatus for producing a motion picture using holographic images. The present invention, it is now believed, is unique in establishing the method for true motion imagery in holograpic processes.